package com.ssy.filter;

import com.ssy.utils.CurrentHolder;
import com.ssy.utils.JwtUtils;
import io.jsonwebtoken.Claims;
import jakarta.servlet.*;
import jakarta.servlet.annotation.WebFilter;
import jakarta.servlet.http.HttpServletRequest;
import jakarta.servlet.http.HttpServletResponse;
import lombok.extern.slf4j.Slf4j;

import java.io.IOException;

import static org.apache.http.HttpStatus.SC_UNAUTHORIZED;

@Slf4j
// @WebFilter(urlPatterns = "/*")
public class TokenFilter implements Filter {

    @Override
    public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {

        HttpServletRequest request = (HttpServletRequest) servletRequest;
        HttpServletResponse response = (HttpServletResponse) servletResponse;
        // 1.获取到请求路径
        String requestURI = request.getRequestURI(); // /login

        // 2.判断是否是登录请求, 如果路径中包含/login, 说明是登录操作, 放行
        if(requestURI.contains("login")) {
            log.info("登录请求, 放行");
            filterChain.doFilter(request, response);
            return;
        }

        // 3. 获取请求头中的token
        String token = request.getHeader("token");
        // 4. 判断token是否存在, 如果不存在, 拦截, 返回401状态码
        if (token == null || token.isEmpty()) {
            log.info("token为空, 响应401");
            response.setStatus(SC_UNAUTHORIZED);
            return;
        }
        // 5. 如果token存在, 校验token, 如果校验失败, 拦截, 返回401状态码
        try {
            Claims claims = JwtUtils.parseJwt(token);
            Integer empId = Integer.valueOf(claims.get("id").toString());
            CurrentHolder.setCurrentId(empId); // 存入
            log.info("当前登录员工的ID： {}，将其存入ThreadLocal", empId);
        } catch (Exception e) {
            log.info("token非法, 响应401");
            response.setStatus(SC_UNAUTHORIZED);
        }
        // 6. 校验通过, 放行
        log.info("token合法");
        filterChain.doFilter(request, response);

        // 删除ThreadLoacl中的数据
        CurrentHolder.remove();
    }
}
